Seasonal and chemotype influences on the chemical composition of Lantana camara L.

Yellow-orange and pink-violet colours of flower plants of Lantana camara from Madagascar were studied with a focus on essential oil (EO) in order to characterize chemotype EO variability. The chemical composition of 73 samples of aerial part EO of L. camara collected each month of the year, at various location, have been characterized by gas chromatography-mass spectrometry (GC-MS). Among the 50 peaks characterized, 43 were identified. The main components changed within the two flower colour types. EO from yellow-orange colour of flowers compared to pink-violet flowers is characterized by high content in terpenic compounds and lower amount in oxygenated compounds. Similar results were observed during seasons, showing that the chemical composition is relatively stable all year long. The components characterizing the pink-violet flower chemotype are: sabinene (9.4-11.3%), 1,8-cineole (3.7-4.6%), linalool (4.8-6.1%), β-caryophyllene (11.3-13.6%), α-humulene (4.4-5.2%), β-bisabolene (1.7-2.3%), γ-cadinene (0.1-0.4%), ar-curcumene (1.0-1.6%), caryophyllene oxide (1.2-0.7%) and davanone (22.6-25.9%). The components characterizing the yellow-orange flower chemotype are: sabinene (9.0-14.3%), 1,8-cineole (0.8-1.0%), linalool (0.4-1.4%), β-caryophyllene (25.8-30.8%), α-humulene (2.4-2.6%), β-bisabolene (13.6-14.9%), γ-cadinene (0.6-5.2%), ar-curcumene (0.7-2.8%), caryophyllene oxide (0.1-0.4%) and davanone (0.0-0.6%). Chemical composition of nine L. camara industrial EO show that they are composed of mixture of yellow-orange and pink-violet colour of flower chemotypes. Davanone is found in all samples with a mean of 12.4%, linalool (5.4%) and 1,8-cineole (4.1%). For sesquiterpenes, the main are β-caryophyllene (15.9%), β-bisabolene (1.8%) and γ-muurolene (1.4%).